I suppose that by "comment sections" you mean your questionnaire contained "Essay box" questions.
The idea behind the "View all responses" feature is to enable individual students to compare their questionnaire answers with those of their fellow students. That's why the feature is default-enabled for the student role in Questionnaire.
Please note that when a student views all their fellow-students' responses, their names are not displayed. Which means that "personal information" cannot normally be related to the actual respondents' identity.
However, if you create a questionnaire that contains Essay box questions and you do not want the answers to such questions to be displayed, then the only way to do this, for that specific questionnaire only, is to set the desired permissions in that questionnaire's permissions. See the steps below.
